www.pudn.com > Nwpro.rar > IGMP.H, change:2003-02-25,size:2812b

/* 
 * Copyright (c) 1988 Stephen Deering. 
 * Copyright (c) 1992, 1993 
 *	The Regents of the University of California.  All rights reserved. 
 * 
 * This code is derived from software contributed to Berkeley by 
 * Stephen Deering of Stanford University. 
 * 
 * Redistribution and use in source and binary forms, with or without 
 * modification, are permitted provided that the following conditions 
 * are met: 
 * 1. Redistributions of source code must retain the above copyright 
 *    notice, this list of conditions and the following disclaimer. 
 * 2. Redistributions in binary form must reproduce the above copyright 
 *    notice, this list of conditions and the following disclaimer in the 
 *    documentation and/or other materials provided with the distribution. 
 * 3. All advertising materials mentioning features or use of this software 
 *    must display the following acknowledgement: 
 *	This product includes software developed by the University of 
 *	California, Berkeley and its contributors. 
 * 4. Neither the name of the University nor the names of its contributors 
 *    may be used to endorse or promote products derived from this software 
 *    without specific prior written permission. 
 * 
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 
 * SUCH DAMAGE. 
 * 
 *	@(#)igmp.h	8.1 (Berkeley) 6/10/93 
 */ 
 
/* Internet Group Management Protocol (IGMP) definitions. */ 
 
/* 
 * IGMP packet format. 
 */ 
struct igmp { 
	u_char		igmp_type;	/* version & type of IGMP message  */ 
	u_char		igmp_code;	/* unused, should be zero          */ 
	u_short		igmp_cksum;	/* IP-style checksum               */ 
	struct in_addr	igmp_group;	/* group address being reported    */ 
};					/*  (zero for queries)             */ 
 
#define IGMP_MINLEN		     8 
 
#define IGMP_HOST_MEMBERSHIP_QUERY   0x11  /* message types, incl. version */ 
#define IGMP_HOST_MEMBERSHIP_REPORT  0x12 
#define IGMP_DVMRP		     0x13  /* for experimental multicast   */ 
					   /*  routing protocol            */ 
 
#define IGMP_MAX_HOST_REPORT_DELAY   10    /* max delay for response to    */